Model: Ensure name is not empty

We don't need it because we don't have to open the new-config UI
after scanning a QR code.

This reverts commit db72e95.

WireGuard/WireGuard/Model/Configuration.swift

@@ -28,6 +28,7 @@ struct InterfaceConfiguration: Codable {
     init(name: String, privateKey: Data) {
         self.name = name
         self.privateKey = privateKey
+        if (name.isEmpty) { fatalError("Empty name") }
         if (privateKey.count != 32) { fatalError("Invalid private key") }
     }
 }